Hello all, would there be any benefit to having a large horn of some sort in front of FR drivers around 1.5" to 3.5"? If there are positives, how about the back of the driver? Is that better enclosed or open?
See the thing is that I actually don’t know what the horn things are all about but a large one sitting on top of a sub would look really cool. So would there be any point in having a FR horn system? I am open to any drivers that would fit such use
I think I am imagining something like a tapered line with a flared mouth and an FR driver mounted somewhere along the line or just an open back. Whatever is aligned for SQ. I have lots of 4mm ply offcuts in a very bendy hardwood called Damanu and a multi-petal build might look very nice
I am stating all the above without any knowledge of what horns are about. Is this a done thing?
I am stating all the above without any knowledge of what horns are about. Is this a done thing?
Well, the second link belongs to the same 'vendors forum' branch, and just look for ob+ flare ( jocking! It must be 'horn') and full range 10 pages thread. It occurs to me that I can do it! So...
https://www.diyaudio.com/community/...-than-box-speakers.407062/page-3#post-7549140
https://www.diyaudio.com/community/...-than-box-speakers.407062/page-3#post-7549140
I remember a speaker like that in a museum in Vancouver. It was a giant back-wave horn, I know nothing about the project. I think the goal was to get as wide a response as possible from a small driver. It sounded good, but couldn’t fit in my living room. Maybe someone else here knows about it.
The ones I remember were very much like the Kleinhorns but bigger and had smooth plywood transitions.
A horn works over typically 3-4 octaves.
So with a FR one has to choose where it makes sense to get more gain.
Most commonly seen are horns that load the back and intend to give bass gain.
Big front loaded horns like the BD or Azura horns for Lowther provide gain in the lower part of their range to help balance the output from a driver that has a seriosu rise with frequency — a direct radiator at HF.
dave
So with a FR one has to choose where it makes sense to get more gain.
Most commonly seen are horns that load the back and intend to give bass gain.
Big front loaded horns like the BD or Azura horns for Lowther provide gain in the lower part of their range to help balance the output from a driver that has a seriosu rise with frequency — a direct radiator at HF.
dave
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Dinsdale’s horn papers particularly paper 2 has some practical advice. No doubt there are other good articles and books.
https://diyaudioprojects.com/Technical/Papers/Horn-Loudspeaker-Design-Part-2.pdf
https://diyaudioprojects.com/Technical/Papers/Horn-Loudspeaker-Design-Part-2.pdf
Thanks for the tip. I came across this
https://www.passdiy.com/pdf/KleinHorn.pdf
Explains that I am looking for an "exponential horn". Even though the drawing up and cutting and construction part of such a shape is well within my experience, the maths to find the lofting for the drawing is not. The maths in the PDF appears to be beyond me. I don't know what all the maths terms are about and how to apply. Even the equation appears to be a foreign language. This places such a project out of my reach unless anyone knows a program that can do the maths for me
Dave, thanks for always trying to make your explanations idiot friendly so even I can try to follow
From what you say and others in this thread and elsewhere, can I work towards the following?
Can a front mounted horn lift the output of a 50mm open back type driver enough from around 200hz-20khz enough to easily follow with an el34 SET amp? If possible with good SQ then I could ask some friends to help with the maths
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The big Oris & Azura style horna reach down to about 300 Hz.
The Oris loads an 8”/200mm Lowther, now extend the top unil it is small enuff to fit a 50mm driver. Note that given the curve the walls of the horn will approach parallel. Now this goes to 300 Hz. You need a mouth that reaches 200 Hz. BIGGER, longer. And a recalacution of the horn profile.
Let’s give it the benefit of the dougbt and you gain gain over 4 octaves. 200>400>800>1.6k>3.2k. You need either a serious rise in the top end (like a typical Lowther), lots of EQ or a combination of both. And in those last 2.5 octave you will likely get a mess from rflrctions of the horn walls.
What kind of sensitivity does this 50mm have? 80dB? You aren’t really increasing that in the top end. If you have to EQ to get it flat, you need more power in the EQed region. EL34 SET have 3-4W? So generously that is 86 dB at clipping. Probably not enuff headroom.
I give the task a poor chance of realization.
dave